Concurrent activities and instructed human fixed-interval performance.
The activity available during an FI schedule decides whether adults act like rule-followers or like animals.
01Research in Context
What this study did
Researchers asked adults to press a button on a fixed-interval schedule. Every 30 seconds the first press paid a nickel.
While they worked, the adults could watch TV, read a book, or sit with no activity. The team recorded response patterns and asked what the adults were thinking.
What they found
TV watchers pressed little at first, then fast at the end. Their response curves looked like animal scallops.
Readers and the no-activity group pressed slowly and steadily. They told the researchers they counted seconds in their heads.
How this fits with other research
Wacker et al. (1985) showed that babies press like pigeons, but older kids press like rule-followers. Tantam et al. (1993) now show that even rule-following adults can flip back to animal-style scallops if TV is present.
Blackman (1970) proved pigeons need added cues to keep scallops. Humans get the same push from TV; reading keeps the verbal rule alive.
Llinas et al. (2022) gave kids continuous toys to cut stereotypy. The idea is shared: what sits beside the schedule shapes the behavior.
Why it matters
Your client’s other activities are not background noise. They can switch rule-governed behavior to habit-style responding. If you want steady, thoughtful work, pick tasks that support inner speech. If you want burst responding, embed high-value screens. Control the context and you control the pattern.
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02At a glance
03Original abstract
Two experiments explored the effects of two types of concurrent activity on human fixed-interval performance. Eight adult subjects were given access to either reading material or a working television set across three fixed-interval values (60 s, 300 s, and 600 s). During Experiment 1, 2 subjects produced "scalloped" patterns and reported no verbal regulation (e.g., counting) in the presence of the reading material, but shifted to low-rate patterns and reported verbal regulation when the reading material was withdrawn. The 2 other subjects in Experiment 1 produced consistent low-rate performances and reported verbal regulation during access to reading material. However, when these subjects were given access to a working television set, they produced scalloped patterns and reported no verbal regulation. During Experiment 2, 4 experimentally naive subjects showed consistent scalloped patterning and no verbal regulation across fixed-interval values when they were allowed to watch television. When access to the television was denied, subjects reliably reported verbal regulation, and low-rate patterns emerged. These behavioral effects focus our attention on the contingencies that control human performance on fixed-interval schedules.
Journal of the experimental analysis of behavior, 1993 · doi:10.1901/jeab.1993.59-501